Splice for crankshaft bearings



y 1949- M. SHULDA 2,471,982

SPLICE FOR CRANKSHAF 'T BEARINGS I Filed NOV. 4, 1946 Maia/in fihulda Patented May 31, 1949 so STATES PATENT OFFICE SPLICE FOR CRANKSHAFT BEARINGS Melvin Shuida, Cuba, Kans.

Application November 4, 1946, Serial No. 707,726

1 Claim. i

Th present invention relates to a crank shaft having three or more crank on wrist pins, and the main object of this invention is now to produce such a machine part in a simple manner to obtain a very strong and durable shaft.

Ifsuch a shaft, for instance, has three crank or wrist pins, the middle wrist pin is always difficult both to forge and to machine. One feature of my invention consists now in making two similar forgings for a three bearing crank shaft and splicing them together in the middle bearing.

These and other features and objects of the invention will be easily understood from the subjoined description with the aid of the attached drawing, which forms a part of the application.

One embodiment of the invention is illustrated in th accompanying drawing, wherein like numerals relate to the same details in the different views.

Figure 1 is an assembled side view, partly in section;

Figure 2 is the left half of the crank shaft;

Figure 3 is the right half of said shaft;

Figure 4 is a cross section along line d-t of Figure 1; and

Figure 5 shows in side elevation the bearing head and cap provided on the end of the pitman.

Numeral it denotes in general the three point bearing of a crank shaft, on which ii is the left side half and E2 the right side half thereof. To produce said shaft, a forging is made for each half, which halves are similar and made from identical forgings. The left half is shown in Figure 2 where the crank or wrist pin is for the left bearing connects with the stub pin i t forming the middle bearing by means of an arm or web l5. This stub end it is cylindrical on the outside of a length corresponding to that of the finished middle crank or wrist pin and has a tapered bore it from its outer end terminating at the flat shoulder l5a of the arm or web IS.

The right hand half of the crank shaft shown in Figure 3 has a similar right side wrist pin I! which connects by means of a web or arm I8 to the stub pin l9 formin part of the middle wrist pin which has a tapered outside surface 16a corresponding to the inside tapering bore I6 of the left half but is of a slightly shorter length than the stub H. Diametrically opposite each other, four splines 20 are provided reaching from the 2 shoulder 2! to near the end of the stub pin l9, and are intended to engage in the grooves 26 provided in the bore l6 of the stub Hi but slightly shorter than stub it. These splines and grooves are correspondingly tapered.

In assembling the two halves of the shaft, an antifriction bearing 23 is pressed on around stub end it. This bearing has a width equal to the. length of the stub it. Care should be taken that the free end of the stub l4 does not abut against the shoulder it. This will require a small gap or space about 9 5 inch to be provided between the end of the right hand bearing pin i9 and the bottom of the tapered bore it of stub M, and also at the shoulder 2i and end of stub it. A tightening screw 22 is threaded in the end of the bearing pin is. This screw is tightly drawn up against the web or arm [5 which has a straight axial hole for the screw 22. This screw 22 also will pull stub pin 89 tightly into bore it of stub it.

The assembly is now carried or supported by the bearing head it the top half of which is forged with the engine block and is provided with a cap 25 and which is to be of equal width with the outside race of bearing 23.

This anti-friction bearing may consist of single or double row ball bearings or roller hearing or Timken roller bearing whichever is found to be more suitable.

It is to be understood that the invention as herein disclosed may be varied from the details described and shown without departure from the spirit of the subjoined claim.

I claim:

A crank shaft wrist pin construction, comprising a crank arm, a stub pin cast integral therewith and having a circular outside cross section. said pin having a free end, a tapered bore formed axially in said pin from the free end thereof, a second crank arm, a pin cast integral with an end of the second arm and tapered for axial insertion into said bore, said bore having a tapered longitudinal spline groove, a tapered spline forming an integral milled part of said tapered pin for engagement in said groove, means for coupling said pins and drawing the ta red pin into the stub pin, each of the crank arms being formed to provide a shoulder face encircling the pin which is integral therewith, and the diameters ottheboreandtaperedplnbelnz suchthat when the tapered pin is firmly 1n the bore of the stub pin the free end 02 the stub plnwlll be closely adjacent to the shoulder adjacent to the tapered pin and the tapered end of the taperedplnwlllbespacedtromthelnnerend of the tapered bore. the said tapered spline groove termlnatln: a substantial distance short or the inner end of the tapered bore and the said tapered spline terminating short or the inner end of the spline groove when the tapered pin is fully inserted into the bore of the stub pin.

MELVIN SHULDA.

4 REFERENCES crrnn 'The following references are of record in the llle of this patent:

UNITED STATES PATENTS 

